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arXiv · 1301.3606

NGC5694: another extra-galactic globular cluster

A. Mucciarelli·M. Bellazzini·M. Catelan·P. Amigo·M. Correnti·C. Cortés·E. Dalessandro·V. D'Orazi
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Abstract

We discuss the chemical composition of six giant stars of the outer Halo globular cluster NGC5694, through the analysis of UVES@FLAMES high-resolution spectra. The cluster has an average iron content [Fe/H]=--1.83+-0.01, solar-scaled [alpha/Fe] ratios and a very low Ba abundance ([Ba/Fe]=--0.71+-0.06). These anomalous abundance patterns are different from those observed in other Halo globular clusters but similar to those of the metal-poor stars in typical dwarf spheroidal galaxies. These findings suggest an extra-galactic origin for NGC5694, likely from a dwarf spheroidal galaxy.

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A. Mucciarelli, M. Bellazzini, M. Catelan, P. Amigo, M. Correnti, C. Cortés, E. Dalessandro, V. D'Orazi. 2013-01-16. NGC5694: another extra-galactic globular cluster. https://arxiv.org/abs/1301.3606

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